In-situ plasma regeneration of deactivated Au/TiO<sub>2sub> nanocatalysts during CO oxidation and effect of N<sub>2sub> content
- 作者：Hong-Yu Fan ; Chuan Shi ; Xiao-Song Li ; Shuo Zhang ; Jing-Lin Liu ; Ai-Min Zhu<sup> ; sup><sup>amzhu@dlut.edu.cnsup>
- 关键词：Gold catalyst ; Deactivation ; Plasma regeneration ; N2 content ; CO oxidation
- 刊名：Applied Catalysis B ; Environmental
- 出版年：2012
- 期刊代码：4_09263373
- 类别：ce
- 出版时间：30 May, 2012
- 卷：119-120
- 期：Complete
- 页码：49-55
- 文件大小：1186 K
摘要
Driven by excellent CO oxidation capability of gold nanocatalysts at room temperature, a TiO<sub>2sub> supported Au nanocatalyst (Au/TiO<sub>2sub>) was synthesized by deposition-precipitation method. To solve the deactivation issue of Au/TiO<sub>2sub> catalyst during CO oxidation, in-situ regeneration by N<sub>2sub>/O<sub>2sub> plasma was employed. Pure O<sub>2sub> plasma could reversibly regenerate the deactivated Au/TiO<sub>2sub> catalyst, however, N<sub>2sub> addition resulted in an extra catalyst poisoning during regeneration. The extra poisoning effect was the most severe at 10%N<sub>2sub> and became much weaker at 80%N<sub>2sub>. To investigate the formation of any surface poisoning species [NO<sub>ysub>]<sub>ssub> on Au/TiO<sub>2sub> catalyst, gaseous product of N<sub>2sub>/O<sub>2sub> plasma over fresh Au/TiO<sub>2sub> catalyst was on-line analyzed by FT-IR, followed by catalyst characterization with temperature programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. The Au/TiO<sub>2sub> catalysts before and after plasma regeneration were also measured by transmission electron microscopy (TEM), in order to exclude the poisoning effect arisen from the change in gold particle size or morphology.